In recent years, studies have been conducted on various methods for producing flexible organic EL devices, which are expected to be applied to next-generation display devices, lighting devices, etc. One of such methods includes the step of applying polyimide or suchlike to a carrier substrate made of glass or suchlike, thereby forming a resin layer, the step of forming an array of light-emitting elements on the resin layer, a laser lift-off step for irradiating the resin layer with a laser beam from the back side of the carrier substrate, thereby breaking the bond between the carrier substrate and the resin layer, and a separation step for separating the unbound substrate and layer (see, for example, Non-Patent Document 1). Note that laser lift-off is also referred to as LLO from the initial letters thereof.
The resin layer separated from the carrier substrate in the separation step is used as an essential part of a flexible organic EL device (final product). On the other hand, the carrier substrate is, for example, discarded.